High BTS fails after HSPA 72 users/cell activation

[rosan]

Hi All,

We have activated 72 HSPA users/cell recently in our NSN network after that HSDPA and HSUPA setup fails due to BTS increased dramatically (also we had max user fails in HSUPA before and it resolved, of course). Also the number of failures are almost equal in HSDPA and HSUPA in most of the cells. Is there any workaround for this?

Thanks

[m121]

Hi, how about CEs, do sites have enought or maybe now there is a lack of them?
Did you try WBTS restart, we have expierenced that after some upgrades etc some sites start to have SW problems and after reset everything goes back to normal.
Did BTS fail increase are in all sites or just in a few? Also after reaching what number for UEs connected ir HSDPA starts hapening BTS failures or they are active all the time, even at 3AM when there are only few users?

[gprastomo]

Instead of CE, also try to check whether the RNC already apply the Dynamic Resource, im affraid the fixed resource will reserve those 72 CE per Cell as ul dpdch return channel will be reserved for HSDPA, so check it in case it affect.

[rosan]

Thanks for your replies. Overall CE utilization is less ~60% and BTS fails triggers only in busy hours.

[elkador]

Are you using RNC MP5 and NodeB MP4.1?
If using older release, you may consider upgrading to those...

[rosan]

Ya. We are using this version of the softwares.

[elkador]

Try reducing the max code available to 14 (instead of 15) on a few sites.
You may see an improvement in stats...

[rosan]

Hi elkador,
It is at 14.
Thanks

[m121]

One more thing that came up in my mind: how about 16kbps return channel. If it's not enabled then UL overload could be the reason.

[paali]

thanx for High BTS fails after HSPA 72 users/cell activation

[jan74]

You can bet your bottom dollar its a software problem. A known issue fixed in the next release.... Have seen it umpteen times.

[elkador]

I agree with this one. Definitively a requirement...


One more thing that came up in my mind: how about 16kbps return channel. If it's not enabled then UL overload could be the reason.

[q15928]

How many HSDPA schedulers are used (check the Tcell setting)? Reduce extra scheduler can save CE as well.

But as I have seen often NSN WBTS will go crazy with high BTS fails. Normally a reset will solve the issue. Otherwise, get the System Module replaced.